Novaturn randomly stops program execution

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torleifj
Posts: 23
Joined: Mon 13 Oct , 2008 15:34 pm
Location: Denmark

Novaturn randomly stops program execution

Post by torleifj » Tue 18 Feb , 2014 22:49 pm

Hi.

My Novaturn/FLSTEP runs fine for a random period of time. Suddenly it stops the spindle and the program execution without any error message. In average, it happens once every hour.

Any ideas how I can debug this?

Best regards,

Torleif.

Martin
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Re: Novaturn randomly stops program execution

Post by Martin » Tue 18 Feb , 2014 23:43 pm

How do you restart it?

torleifj
Posts: 23
Joined: Mon 13 Oct , 2008 15:34 pm
Location: Denmark

Re: Novaturn randomly stops program execution

Post by torleifj » Wed 19 Feb , 2014 0:26 am

I would prefer a better way, but this is how I do: I switch to jog mode, set speed and feed, start the spindle, switch back to auto and press cycle start.

When the program ends, it jumps back to the place in the program where I restarted it, so I have to scroll back to the start or reload the program.

Martin
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Re: Novaturn randomly stops program execution

Post by Martin » Wed 19 Feb , 2014 7:48 am

It does sound strange.

How about unplugging the RS232 lead at both ends, moving it away from other wires & reconnecting it.

It does sound as though it is a electrical noise issue.

torleifj
Posts: 23
Joined: Mon 13 Oct , 2008 15:34 pm
Location: Denmark

Re: Novaturn randomly stops program execution

Post by torleifj » Wed 19 Feb , 2014 11:03 am

Good point. I'll give it a try and order an optical RS232 isolator.

torleifj
Posts: 23
Joined: Mon 13 Oct , 2008 15:34 pm
Location: Denmark

Re: Novaturn randomly stops program execution

Post by torleifj » Sun 23 Feb , 2014 23:39 pm

Now I have separated the wires and added an RS232 isolator. It still stops.

Is there any thermal protection that could trip after an hour of operation?

Martin
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Re: Novaturn randomly stops program execution

Post by Martin » Mon 24 Feb , 2014 7:38 am

Yes depending on which spindle motor is fitted. If you have the SEM spindle motor it does have a thermal but it would not restart until the temp had dropped which may take a fee mins.

torleifj
Posts: 23
Joined: Mon 13 Oct , 2008 15:34 pm
Location: Denmark

Re: Novaturn randomly stops program execution

Post by torleifj » Mon 24 Feb , 2014 17:18 pm

Hmm. I think we can rule that one out. This morning it stopped a few minutes after start. And there is no restart delay.

torleifj
Posts: 23
Joined: Mon 13 Oct , 2008 15:34 pm
Location: Denmark

Re: Novaturn randomly stops program execution

Post by torleifj » Sat 01 Mar , 2014 22:22 pm

It will be wrong to say that I cured the problem, but now the machine no longer stops.

A week ago, I did some parts with a vacuum cleaner installed to grab some very long chips. It was as if it increased the time between failures. Still, it's only statistics. It may be a coincidence.

Today the machine ran well for the first hour, then it was unable to complete any 15 minutes CNC run. I temporarily installed a large fan that cools the machine (not the control). It has now run for 2 hours without a single stop.

It is always on, so steppers are always hot. It typically does 15 minute jobs and I restart it as soon as it finishes.

Does it make sense that cooling will stabilize the machine?

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